25784: She took pills and her period became irregular

A woman took pills and had an injection to prevent pregnancy, which led to her menstrual cycle becoming irregular. So now she bleeds for ten days, which is how long her period used to last, then she is pure (i.e., doesn’t bleed) for ten days, then she starts to bleed again as before, and so on. What is the shar’i ruling in this case?

Praise be to Allaah.

If a woman’s menstrual cycle is irregular, then she should
distinguish between the kinds of bleeding. When she sees menstrual blood,
which is “black” blood (i.e., very dark red), recognizable and has a
distinctive odour, then she should stop praying etc. until she becomes
pure.